At very small dimensions, this calculation could lead to zero-sized
filters, which leads to uninitialized output, zero-sized allocations,
loop overflows in SIMD that uses do{..}while(i++<filtersize); instead
of for(i=0;i<filtersize;i++){..} and several other similar failures.
Therefore, require a minimum filtersize of 1.
Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
CC: libav-stable@libav.org
This fixes integer multiplication overflows in RGB48 output
(vertical) scaling as detected by IOC. What happens is that for
certain types of filters (lanczos, spline, bicubic), the
intermediate sum of coefficients in the middle of a filter can
be larger than the fixed-point equivalent of 1.0, even if the
final sum is 1.0. This is fine and we support that.
However, at frame edges, initFilter() will merge the coefficients
for the off-screen pixels into the top or bottom pixel, such as
to emulate edge extension. This means that suddenly, a single
coefficient can be larger than the fixed-point equivalent of
1.0, which the vertical scaling routines do not support.
Therefore, remove the merging of coefficients for edges for
the vertical scaling filter, and instead add edge detection
to the scaler itself so that it copies the pointers (not data)
for the edges (i.e. it uses line[0] for line[-1] as well), so
that a single coefficient is never larger than the fixed-point
equivalent of 1.0.
This was removed erroneously in
046f081b46. This define still is
necessary for getting MAP_ANONYMOUS defined on linux/glibc,
despite the define reshuffling done in that commit.
Without MAP_ANONYMOUS defined, the mprotect calls for setting the
generated mmx2 scaler code pages executable are left out, causing
crashes if that codepath is chosen.
This patch fixes scaling from 192x144 to 320x240 with
-sws_flags fast_bilinear, which crashes on linux at the
moment.
Signed-off-by: Martin Storsjö <martin@martin.st>
libswscale/utils.c:941:13: warning: passing argument 5 of ‘initMMX2HScaler’ from incompatible pointer type
libswscale/utils.c:524:12: note: expected ‘int32_t *’ but argument is of type ‘int16_t *’
libswscale/utils.c:942:13: warning: passing argument 5 of ‘initMMX2HScaler’ from incompatible pointer type
libswscale/utils.c:524:12: note: expected ‘int32_t *’ but argument is of type ‘int16_t *’
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
Altivec does unaligned reads from this buffer in
hscale_altivec_real(), and can thus read up to 16 bytes beyond
the end of the buffer. Therefore, add an extra 16 bytes of
padding at the end of the conversion buffer.
This fixes fate-lavfi-pixfmts_scale on AltiVec-enabled builds
under valgrind.
Signed-off-by: Ronald S. Bultje <rsbultje@gmail.com>
SSE-optimized hScale() scales up to 4 pixels at once, so we need to
allocate up to 3 padding pixels to prevent overreads. This fixes
valgrind errors in various swscale-tests on fate.
The logged information is possibly false, and it tends to be outdated
after each change since the logging code needs to be manually updated.
Simplify and prevent confusing wrong debug messages.
Signed-off-by: Luca Barbato <lu_zero@gentoo.org>
Also remove the unnecessary isSupportedIn/Out macros.
Make the code more compact/readable, and simplify the access to
lsws-specific pixel format information.
Signed-off-by: Luca Barbato <lu_zero@gentoo.org>
Michael Niedermayer
Ronald S. Bultje
Carl Eugen Hoyos
Alex Converse
Paul B Mahol
Diego Biurrun
Reinhard Tartler
Martin Storsjö
Sean McGovern
Anton Khirnov
Reimar Döffinger
Jean First
Stefano Sabatini